Apparatus for bending a casting having a liquid core



J. E. FOLDESSY Sheet Fig.1

INVENTOR.

vs S y E E D M L O O F n e fl m T s U J June 3, 1969 APPARATUS FORBENDING A CASTING HAVING A LIQUID CORE Original Filed March 6, 1964 3 HL .y w M N June 3, 1969 J. E. FOLDESSY APPARATUS FOR BENDING A CASTINGHAVING A LIQUID CORE oiiginal Filed March 6. 1964 Sheet INVENTOR. JUSTINE.FOLDESSY ATTORNEY June 3, 1969 J. E. FOLDESSY 3,447,591

APPARATUS FOR BENDING A CASTING HAVING A LIQUID coma Original FiledMarch 6. 1964 Sheet 3 of 10 INVENTOR. JU STIN E. FOLDESSY ATTORNEY June3, 1969 J. E. FOLDESSY APPARATUS FOR BENDING A CASTING HAVING A LIQUIDCORE Sheet Original Filed March 6, 1964 JUSTIN E- FOLDESSY M $79-ATTORNEY June 3, 1969 J. E. FOLDESSY APPARATUS FOR SENDING A CASTINGHAVING A LIQUID CORE Sheet Original Filed March 6, 1964 INVENTOR JUSTINE. FOLDESSY M ATTORNEY June 3, 1969 J. E. FOLDESSY APPARATUS FOR BENDINGA CASTING HAVING A LIQUID CORE Sheet Original Filed March 6. 1964INVENTOR.

.JUSTIN E. FOLDESSY M/M A TT( JR NE y June 3, 1969 J. E. FOLDESSYAPPARATUS FOR BENDING A CASTING HAVING A LIQUID CORE Sheet OriginalFiled March 6. 1964 INVENTOR. JUSTIN E1 FOLDESSY Wj M ATTORNEY June 3,1969 J. E. FOLDESSY 3,447,591

APPARATUS FOR BENDING A CASTING HAVING A LIQUID CORE Original FiledMarch 6. 1964 Sheet 6 of 10 Fig.8

INVENTOR.

JUSTIN E. F OLDESSY BYMkM June 1969 .1. E. FOLDESSY 3,447,591

APPARATUS FOR BENDING A CASTING HAVING A LIQUID CORE Original FiledMarch 6, 1964 Sheet 9 of 10 INVENTOR. JUSTIN E. FOLDESSY KMXM ATTORNEYJune 3, 1969 J. E. FOLDESSY 3,447,591

APPARATUS FOR BENDING A CASTING HAVING A LIQUID CORE Original FiledMarch 6, 1964 Sheet M of 10 INVENTOR.

JUSTIN E.FOLDESSY g law/M a ATTORNEY United States Patent 3,447,591APPARATUS FOR BENDING A CASTING HAVING A LIQUID CORE Justin E. Foldessy,Ogden Dunes, Ind., assignor to United States Steel Corporation, acorporation of Delaware Original application Mar. 6, 1964, Ser. No.349,944, now Patent No. 3,338,297, dated Aug. 29, 1967. Divided and thisapplication Feb. 10, 1967, Ser. No. 615,196 Int. Cl. B22d 11/12, 27/04US. Cl. 164282 2 Claims ABSTRACT OF THE DISCLOSURE An apparatus formoving a continuopsly formed casting in a continuous metal castingapparatus. A plurality of pinch rollers are arranged in two pairs belowthe cooling mold and above a guide mechanism for guiding the castingfrom a vertical path to a lateral path. The idler rolls of the pinchrollers engaging the casting are driven by through backup rolls. Also,the top pinch rolls are driven at a higher speed than the lower pinchrolls to force the casting against the starter bar immediately prior toseparation.

Cross reference to related application This application is a division ofmy copending application Ser. No. 349,944, filed Mar. 6, 1964, nowPatent No. 3,338,297, issued Aug. 29, 1969.

Background of the invention This invention relates to a method andapparatus for continuous casting, especially to a novel method forbending and guiding a continuously formed casting in a curved pathbefore the core of molten metal is solidified and to apparatus therefor.

It is customary in the continuous casting of metals to provide anapparatus comprising a vertical tubular mold open at the upper end forreceiving molten metal and open at the lower end for the discharge of ametal casting, cooling means comprising a plurality of water sprayslocated below the mold for directing cooling water against the castingas it descends vertically, guide means comprising a plurality of guiderolls, located between the water sprays, for guiding the castingvertically as it moves downwardly through the cooling zone, and motordriven pinch rolls located below the guide rolls for controlling therate of descent of the casting. The cooling means are mounted on asuitable immovable frame. The guide rolls and pinch rolls are mountedfor rotation in suitable mountings, which are also mounted on animmovable frame.

As the casting emerges from the discharge opening of the mold, it has asolidified metal skin around its periphery but has a liquid core ofsubstantial volume. This liquid core is gradually solidified as thecasting descends through the cooling zone. By the time the castingreaches the bottom of the cooling zone and passes through the pinchrolls in the usual apparatus, the liquid core is nearly solidified.

It is necessary to close the lower discharge end of the mold initiallywhen molten metal is being poured into the mold. This is usually done bythe insertion of a starter bar into the bottom of the mold. The starterbar is an elongated metal bar, usually rigid, which has across-sectional shape approximately the same as that of the mold with aslightly smaller cross-sectional area in order to permit ready insertionof the bar upwardly through the guide rolls and into the bottom of themold. The starter bar, in addition to closing the discharge end of themold while molten metal is being poured, also supports the 3,447,591Patented June 3, 1969 metal column or casting as it descends through theguide rolls and pinch rolls.

After the starter bar has passed through the pinch rolls, it is severedfrom the casting. This is conventionally done by means of one or morecutting torches located a short distance below the pinch rolls. Thesetorches cut the casting a short distance above the top of the starterbar. The starter bar, with a short length of casting atattached to thetop thereof, is lowered vertically, supported by a suitable platform,basket, or the like. At the bottom of its vertical travel, the starterbar is lowered to a horizontal position and transported horizontallyaway, by power driven rollers for example. The short length of castingattached to the starter bar must be removed before the starter bar canbe used again.

II he casting (excluding the short length which remains attached to thestarter bar) after its severance from the starter bar is generallyhandled in either one of two different ways. According to one mode ofoperation, the casting is cut into lengths by means of the abovementioned cutting torches. Each cut length of casting is then loweredvertically and laid down to the horizontal position and transported awayin the same manner as the starter bar. According to a second mode ofoperation, the casting after severance from the starter bar is deflectedfrom its vertical path by a horizontally reciprocable roll known as apusher roll, and guided in a curved path as it is bent from its initialvertical direction to a horizontal direction by means of a stationaryguide frame having a plurality of guide rolls beneath the casting forsupporting it. When the casting reaches a horizontal direction, it isstraightened out by conventional means, such as straightening rolls. Thecasting after straightening may be reheated if necessary and rolled, orotherwise treated in any desired manner.

Both of the two above modes of operation and the apparatus associatedtherewith contemplate that the casting will be completely or at leastnearly solidified by the time it passes through the pinch rolls. It isessential that the casting be completely solidified before it is cutwith a cutting torch in order to detach the starter bars; otherwise theliquid metal in the core of the casting would fiow out when the castingis cut,

The present methods and apparatus for continuous casting of metals andparticularly of iron and steel, have the disadvantage that a tower ofconsiderable height is required in order to provide a vertical coolingzone of adequate height for solidifying the casting completely. Tominimize the unwieldy height of the cooling zone, it is desirable tocool the casting partially during its vertical descent, to solidify onlypart of the molten metal core, and thereafter completing solidificationwhile the casting is being bent from the vertical to a horizontaldirection.

A further disadvantage of present continuous casting apparatus is that ashort length of casting remains attached to the starter bar aftercutting and must be separated before the starter bar can be used again.

Summary of the invention In order to bend a casting and to disconnectthe same from the starter bar without the necessity of cutting thecasing with cutting torches I have invented, a novel type of starter barwhich can be completely disconnected from the casting without severanceor any part of the casting remaining attached to the starter bar isessenial. Presently known rigid starter bars cannot be used with thisinvention because these have to be severed from the casting.

It is an object of this invention to provide a continuous castingapparatus which includes a casting guide frame especially designed forguiding a casting having a core of molten metal in a curved path.

3 Another object of this invention is to provide novel casting guideframe structures which are especially suited for guiding a castinghaving a molten metal core in a curved path.

Brief description of the drawings This invention will now be describedwith reference to the accompanying drawings in which:

FIG. 1 is an isometric and schematic view of the apparatus of thisinvention;

FIG. 2 is a side sectional view of the apparatus for bending thecasting;

FIG. 3 is a view taken along the line 33 of FIG. 2;

FIG. 4 is a side elevation showing a curved guide frame according to oneembodiment of the invention;

FIG. 5 is a cross section taken along the line 5-5 of FIG. 4;

FIG. 6 is a side elevation of a curved guide frame according to a secondembodiment of this invention;

FIG. 7 is a side elevation of a third embodiment of this invention;

FIG. 8 is a side elevation of a curved guide frame according to a fourthembodiment of this invention;

FIG. 9 is an isomeric view, with parts cut away and parts shown insection, of a starter bar which is useful in the apparatus of thisinvention;

FIG. 10 is taken along the line Ill-10 of FIG. 9;

FIG. 11 is a detail perspective view of a pin for anchoring the castingto the chill plate; and

FIG. 12 is an electrical circuit diagram of an actuation system forautomatically disconnecting the starter bar from the chill plate andcasting when the starter bar reaches a predetermined elevation.

Description of the preferred embodiment for the introduction of moltenmetal to form a casting and a lower discharge opening through which saidcasting may descend continuously as it is formed. The mold may be of anycross-sectional shape desired, but for purposes of illustration arectangular mold is shown.

It is necessary to close the lower discharge passage of mold 20 prior tothe pouring of molten metal therein. A chill plate 24 which is initiallyreleasably secured to a starter bar 26 as shown in FIG. 9 constitutes amember for initially closing the mold and for forming a surface againstwhich the molten metal of the casting solidifies after it is poured intothe mold. An exemplary embodiment of this chill plate and starter barwill be described later with reference to FIGS. 9 to 11 inclusive. Thechill plate 24 and the starter bar 26 releasably secured thereto areinitially inserted into the lower end of the mold so as to close thelower discharge opening. Molten metal is then poured into the upperopening of passage 22 until the metal reaches a predetermined depthwithin mold 20. The outer surface of molten metal abutting tubular mold20, and the lower surface of molten metal abutting chill plate 24,solidify while still in the mold and before descent of the starter barbegins. Means which will be described in detail with reference to FIGS.9 to 11 provide a firm interlocking grip between chill plate 24 and thesolidified lower end of the metal casting. After the depth of moltenmetal in the mold has reached a predetermined level near the top, thestarter bar, chill plate, and casting attached thereto are lowered.

A plurality of guide rolls 30 are located directly below a dischargepassage of the mold for guiding the starter bar and the casting in avertical path as they descend. Such guide rolls are well known incontinuous casting apparatus.

Also located below mold 20 is a cooling means comprising a plurality ofspray nozzles 34 which are supplied with water through headers 36. Thespray nozzles 34 are 4 directed against the opposite faces of thecastings, and are positioned to direct their streams of water betweensuccessive guide rolls 30. The structure of water spray nozzles andheaders for continuous casting apparatus is known in the art, and any ofthe known structures may be used here.

The spray nozzles 34 and guide rolls 30 together constitute a verticalcooling section in which at least a part of the molten metal in the coreof the casting is solidified. An important difference between thisvertical cooling section and vertical cooling section of a conventionalcontinuous casting apparatus is that the length of the cooling sectionin this apparatus will be less than that necessary for completesolidification of the casting under conventional casting conditions.

A pair of pinch roll assemblies 40 and 42 are located at predeterminedelevations below guide rolls 30 and spray nozzles 34. Each of the pinchroll assemblies comprises a pair of large driven rolls 44 and aplurality of smaller idler rolls 46 which are arranged to bear againstthe opposite faces of the casting and to exert a force against thecasting so as to control the rate of its descent. In addition to theidler rolls 46, additional rolls 48 may be located between the drivenrolls 44 and the rolls 46 which bear against the faces of the casting.

An actuation system 50 is located between upper pinch roll assembly 40and the lower pinch roll assembly 42 for releasing starter bar 26 fromchill plate 24 when the starter bar reaches the predetermined elevationat which the actuating means 50 is located. Suitable actuating means arefully described in the copending applications of Justin E. Foldessy andFrancis Gallucci, Ser. No. 333,383, filed Dec. 26, 1963, now Patent No.3,266,104 issued Aug. 16, 1966, and Justin E. Foldessy and Andrew L.Poulos, Ser. No. 333,449, filed Dec. 26, 1963, now Patent No. 3,274,-653, issued Sept. 27, 1966. The operation of this actuating means willbe described in further detail with particular reference to FIG. 12.

The bending means, indicated generally at 60, is located below the lowerpinch roll stand 42. The purpose of this bending means is to bend thecasting and deflect it from its vertically downward path in a laterallyextending direction. The amount of deflection imparted by bending means60 is small but is sufliicent to facilitate the guiding of the castingin a curved path as it continues to descend. This bending means 60includes a stationary roll assembly 62, and a movable roll assembly 64which is movable through a small are about a pair of axially alignednon-rotating shafts 66 which are journaled in stationary roll assembly'62 so as to permit unimpeded'vertical descent of the starter bar 26 ina first position and to initiate the deflection of the casting from itsinitial vertical direction to a direction which is genetrally verticalbut with a small horizontal component when in its second position.Bending means 60 also includes a hydraulic cylinder 68 for moving thebending means between the two positions, and a locking means indicatedgenerally at 70, comprising a pair of pivot pins 71, a pair of arms 72pivotally secured at one end to pivot pins 71 and at the oppoiste end toa shaft 74, which is held in place between a back-up plate 76 having setscrews 77 therein, and vertically reciprocable wedge 78 which can bemoved up and down by hydraulic cylinder 79, so as to lock the movableframe member 64 in position.

The starter bar 26 continues its straight downward course after it isreleased from the chill plate 24 and casting attached thereto by theoperation of actuation mechanism 50. As indicated in the last paragraph,bending means 60 is in its first position as the starter bar descends. Avertically traveling receptacle 80 receives starter bar 26 during itsvertical descent below the bending mechanism 60 and lowers the starterbar to a predetermined level. When the traveling receptacle 80 reachesthe bottom of its travel, the starter bar 26 is received by a tilterframe 82 which lowers it to the horizontal position, and

it is then conveyed away on horizontal conveyor -84, for reuse ifnecessary. The traveling receptacle 80, tilter frame 82, and horizontalconveyor 84 are all known in the art, and further details will not begiven here.

The apparatus of this invention includes a novel casting guide means 90which guides the casting in a curved path from the generally verticaldirection in which the casting is traveling as it emerges from bendingmeans 60. The casting guide means 90 is preferably located immediatelybelow bending means 60 so that the casting its continuously supportedand guided as it descends from the bending means to the casting guidemeans. This guide means 90 includes an upper movable section 92 and alower fixed section 94. The upper movable section 92 is pivotable aboutpivot pins 95 which are located at thte bottom of this section. Each ofthe sections 92 and 94 of guide means 90 includes a plurality of rolls96, the axes of which are arranged along two curved lines definingtherebetween a curved path for the casting, and a plurality of spraynozzles 100 which are supplied with water through headers 102. As thecasting is guided in a curved path in its descent through guide means90, it is further cooled by water issuing through the spray nozzles 100and is completely solidified.

The upper movable section 92 is movable between a retracted positionshown in dot and dash lines in FIG. 4, in which the starter bar 26 maybe brought vetrically downwardly without interference from the guidesection, and a normal operating position which is shown in solid linesin FIG. 4, in which the upper guide section is adapted to receive andguide the casting as it descends below the bending means 60. The upperguide section 92 in its second position provides a curved path for thecasting from bending means 60 to the fixed guide section 94. Movement ofthe upper section 92 is accomplished by means of hydraulic cylinder 104having a piston rod 106 which is attached to the movable section 92 bymeans of an attaching bracket 108. Counterweights 110 facilitatemovement of the movable section 92 from normal to retracted position soas to lessen the amount of force which has to be exerted by hydrauliccylinder 104. In addition the counterweights will minimize the shock inpositioning table from the retracted to the normal position. Thecounterweights are attached to cables 112 which are attached at theiropposite ends to casting guide frame section 92 by means of attachingbrackets 114. Cables 112 pass over pulleys 116.

The casting is traveling in a curved path as it emerges from the loweror discharge end of fixed section 94 of guide means 90. It may then beprocessed further as desired. I

Various embodiments of the curved guide section 90 may be made withinthe scope of this invention. Four such embodiments will be described indetail with particular reference to FIGS. 4 and 5, 6, 7, and 8,respectively.

Referring now to FIGS. 2 and 3, the stationary roll assembly 62 inbending means 60 includes a box type fixed frame 130 having bearings 134which receive guide rolls 136 which bear against the two opposed facesof the casting as it descends. Guide rolls 136 are arranged in a pair ofrows 136a and 13612 which bear against the two opposite faces of thecasting. The upper rolls in row 136a are aligned so that the lines alongwhich each of these rolls contact the casting lie in a vertical plane.The rolls in the lower portion of row 136a are aligned so that the linesof contact between these rolls and the casting define a curved surfacehaving a large radius of curvature with the center to the right as seenin FIG. 4. The opposed row 1361; of rolls, which is to the left as seenin FIG. 4, consists of several rolls aligned to form a vertical plane.The guide rolls 136 are supported against outward bending by a pluralityof back-up rolls 138, which are journaled on stub shafts 140. Shafts 140are supported by bifurcated brackets 142 and held in place by keys 144.The fixed box type frame 130 supports guide rolls 136a and 13611 as wellas back-up rolls 138. The guide roll bearings 134 are mounted directlyon the frame 130. The stationary roll assembly 62 is also provided witha pair of water headers 154 having a plurality of spray nozzles 156projecting therefrom. The water spray nozzles 156 are arranged so as toproject their streams of water between adjacent rolls 136.

The structure of the movable roll assembly 64 is generally similar tothat of stationary roll assembly 62. Movable roll assembly 64 includes amovable frame 160 and the assembly 64 is pivoted about a pair of axiallyaligned non-rotating shafts 66. Shafts 66 are placed in bushing 164,which in turn is placed in bearings 166, integrally connected to frame160. These shafts 66 also extend through sleeves 168 in the fixed frame130 and locked in position by keys 169.

Movable roll assembly 64 has a plurality of guide rolls 170 which arejournaled in bearings 172 secured in side walls of frame 160. The linesof contact between rolls 170 and the casting form a curved surfacehaving a large radius of curvature. When movable roll assembly 64 is inits first position, these rolls are in such a position that they do notinterfere with the vertical downward travel of starter bar 26. Whenmovable roll assembly 64 is in its second position, these rolls initiatethe bending of the casting from its vertical downward path to a curvedpath. A plurality of back-up rolls 174 journaled on stub shafts 176support the guide rolls 170 at spaced intervals to prevent bending.Shafts 176 are supported by bifurcated brackets 178 and held in place bykeys 182. Movable roll assembly 64 has a water header 190 having aplurality of spray nozzles 192 projecting therefrom to direct coolingwater against the casting. These spray nozzles are arranged to projecttheir streams of water between adjacent rolls Movable roll assembly 64is rotated through a small are about the axles 66 by means of hydrauliccylinder 68. The hydraulic cylinder is mounted on a fixed platform 194by means of pivot ears 196. Hydraulic cylinder 68 has a piston (notshown) and a piston rod 198 which projects externally therefrom and isfixedly attached to frame 186 of movable roll assembly 64 by means ofpivot ears 200. When movable roll assembly 64 has been moved to theselected position, it is secured in place by means of locking structure70. The back-up plate 76 is bolted to beam 202, which is part of thestationary supporting structure. Screws 77 limit the position of shaft74. The travel of wedge 78 is controlled by the position of the pistonin cylinder 79. This cylinder has a piston rod 204 which limits themovement of wedge 78. Cylinder 79 is fixedly mounted on bracket 206.Adjusting screws 207 and 208 are provided for initially aligning fixedroll as sembly 62. The movable roll assembly may be locked in eitherretracted position for permitting vertical descent of a starter bar orcasting, or normal position for initiating the deflection of the castinginto a curved path as it descends by appropriate movement of wedge 78and shaft 74.

Referring now to FIGS. 4 and 5, a casting guide means includes a movableupper guide frame 92 and a lower fixed guide frame member 94 as alreadyexplained. The movable guide frame member 92 is a four-sided enclosedstructure having a pair of side walls 210 and a pair of end walls 211and 212. The lower end wall 211, which lies beneath the curved path ofthe casting, is a relatively thin curved Wall of steel plate, andparallel to the curved path of the casting. Upper end wall 212, whichlies above the curved path of the casting, is also a relatively thinsteel plate wall. The guide section 92 has a plurality of guide rolls213 which guide the casting in a curved path. The axes of guide rolls213 lie along a pair of curved lines which define the curved path of thecasting therebetween. Guide rolls 213 are journaled in bearings 214,which are eccentrically mounted in chocks 215. Chocks 215 are held inhousings 216. Centering rolls 225 can be provided if desired. Separatorbeams 226 are secured to housings 216 for alignment of the guide frame92. A pair of water headers 227 are fixedly mounted On beams 226'. Thesewater headers supply a plurality of spray nozzles, 228, which arearranged to direct streams of cooling water against the casting andbetween successive guide rolls 213. An inspection door 229 in side wall212 may be provided.

Pivotal movement of frame 92 about pivot pin 95 is provided by hydrauliccylinder 104, which has a piston rod 106 attached to a mounting bracket108 which is in turn attached to frame 92. Cylinder 104 is mounted on asuitable'fixed structural framework member such as I- beam 105.

Movable frame member 92 is movable between a retracted position, shownin the dotted lines of FIG. 4, which permits unimpeded vertical descentof starter bar 26, and a normal operating position, shown in the solidlines of FIG. 4, wherein the upper end of this frame member 92 ispositioned directly below the lower end of bending means 60 so as toprovide a continuous curved path for the casting as it descends. Bendingof the casting is initiated by the bending means 60. When the castingemerges from the bending means 60 and enters guide frame member 92 itconforms to the curved path of guide rolls 213.

Fixed guide frame member 94 is supported by a fixed structural framework234. This fixed guide frame member 94 is virtually identical to themovable guide frame member 92, and hence a cross-sectional view and adetailed description of this frame member are omitted. Fixed framemember 94 is an enclosed four-sided structure having a plurality ofguide rolls 235, a first pair of sides 236 perpendicular to the axes ofthe guide rolls, and a second pair of sides 237 intersecting sides 236and lying generally parallel to the guide rolls. The axes of guide rolls235 as shown in FIG. 4 lie along a pair of curved lines which definetherebetween a path for the casting as it descends. The lines of contactbetween the guide rolls 235 and the descending casting form a pair ofgenerally curved surfaces which define a curved path for the casting.The casting as it emerges from the bottom of guide frame 94 is travelingin an oblique direction having a substantial horizontal component. Guideframe 94 is also provided with a pair of water headers 238 having aplurality of spray nozzles 239 for directing cooling water against thecasting to complete solidification before it emerges from the lower endof fixed guide frame 94. The streams of water emerging from nozzles 239are directed between successive guide rolls 235.

Referring now to FIG. 6, there is shown a second embodiment of the guideframe according to this invention. This embodiment, designated generallyas 240, includes a movable guide frame member 242 and a fixed guideframe member 94. The fixed guide frame member 94 in this embodiment issimilar to that shown in the embodiment of FIG. 4.

Movable guide frame member 242 is reciprocable between a retractedposition, shown in dotted lines, and a normal position, shown in solidlines in FIG. 6. Reciprocating movement is provided by a hydrauliccylinder 244 having a piston rod 246 extended therefrom and connected toa mounting bracket 248, secured to the side walls of frame member 242. Apair of tracks 250 secured to framework 242 ride on flanged wheels 254which are journaled in mounting brackets 256 which are secured to thefixed structure framework 220.

The structure of guide frame 242 is generally similar to that of guideframe 92 illustrated in FIG. 4, the only essential difference being themanner of movement. Guide frame 242 is an enclosed four-sided structurehaving a pair of side walls 260 in which a plurality of guide rolls 262are journaled. Guide rolls 262 are arranged in a pair of curved rows,their axes lying along a pair of curved lines defining a path for thecasting therebetween. The lines of intersection between the guide rolls262 and the surfaces. The other two side walls 264 intersect side walls260 and are generally parallel to guide rolls 262. A pair of waterheaders 266 having a plurality of spray nozzles 268 are provided fordirecting cooling water against the casting.

When the movable guide frame memebr 242 is in the retracted positionshown in dotted lines, the starter bar 26 is free to descend verticallywithout interfering with this guide frame member. When the guide framemember is moved to the normal position, shown in solid lines in FIG. 6,it receives the casting as it emerges from bending means 60 while it istraveling substantially vertically, and guides the casting in a curvedpath. The movable frame member 242 in its normal position, and the fixedframe member 94 cooperate to provide a single continuous curved path forthe casting.

Guide frame 270 according to the third embodiment of the invention,shown in FIG. 7, comprises a movable rigid frame 272 and a fixed rigidframe 274. The frame 270 of this embodiment is similar to frame 240 as.shown in FIG. 6, except that a portion of the frame structure which isincluded. in movable frame memebr 242 in FIG. 6

is a part of fixed frame 274 in this embodiment. The movable rigid frame272 is an open three-sided structure hav- I face of the casting. Guideframe 272 is reciporcable be-- tween the retracted position, shown indotted lines, which permit unimpeded vertical descent of the starterbar, and the normal position, shown in solid lines, in which guide frame272 cooperates with guide frame 274 to provide a curved path for thecasting as it descends. The structure for accomplishing reciprocatorymovement of guide frame 272 is similar to that for moving guide frame242 in FIG. 6 and consists of a hydraulic cylinder 244 having piston rod246 attached to mounting bracket 248 of frame 272. A pair of tracks 250secured to frame 272 ride on flanged wheels 254 which are mounted onbrackets 256 for guiding the movement of curved guide frame 272.

Guide frame 274 consists of an upper portion 285 and a lower portion286. Frame portion 286 is a four-sided structure having a pair ofopposed side walls 288 and a pair of curved side walls 290 and 292 whichare generally parallel to the path of the casting, and axes of guiderolls 280. Side 290 extends the entire height of fixed upper portion285. Side 292 extends only below the lower portion 286 of frame member274 and its upper end terminates at the lower end of movable framemember 272. Only the lower portion 286 is an enclosed four-sidedstructure. The upper portion 285 is a three-sided structure which iscomplementary in shape with movable frame member 272. Frame member 274has guide rolls 293 arranged in two curved rows 293a and 293b forguiding the opposite faces of the casting. Row 293a lies entirely in thelower portion of the frame and is a continuation of row 280 in movableframe member 272 when that framemember is in operating position. Row293b extends the entire length of frame 274. Frame 274 has a waterheader 300 which lies parallel and close to side wall 290, and a secondwater header 302 which lies parallel and close to side wall 292. Each ofthese headers has a plurality of nozzles 304 projecting laterallytherefrom and adapted to spray cooling water against the casting.

Referring now to FIG. 8, there is illustrated a fourth embodiment of thepresent invention. In this embodiment there is a movable guide framesection 310 and a fixed guide frame section 312 therebelow. Fixed guideframe 9 section 312 is structurally similar to guide frame section 94 inthe embodiments of FIGS. 4 and 5 except for the presence of an outwardlyextending guide flange 314 near the top thereof for guiding the movablesection 310 as will be hereinafter explained.

Movable guide section 310 comprises a chain 320 arranged at each sidehaving a plurality of links therein. Pivotally attached toeach link is aguide section 322 having one pair of rolls 324 journaled in said guidesection and adapted to bear against the opposite faces of the casting.Each of the guide sections 322 also includes water spray nozzles 326adjacent one end thereof, arranged to direct streams of water againstthe casting without striking guide rolls 324. In other words, each ofthese streams of cooling water is directed between the guide roll 324 inthe guide section supporting said nozzle and the corresponding guideroll in the adjacent guide section. Each of the guide sections 322extends transversely of chain 320 on either side thereof.

The top of guide section 310 has a supporting structure 328 forsupporting chain 320. This supporting structure 328 is a suitablydesigned structure having a top surface 330 and a pair of side walls 332extending downwardly therethrough. This structure 328 is fixedly securedto a fixed rigid supporting structure denoted herein by a pair ofchannel sections 334. A pin 336 or number of pins extending through eachside wall 332 supports chain 320. When no lateral force is applied toframe member 310, it hangs freely in a vertical position, and in thisposition permits unimpeded descent of the starter bar. The frame member310 can be moved by a suitable supporting member or pusher 340 to normalposition, in which the frame assumes a curved shape and in which thelower end of frame 310 is in alignment with fixed frame 312 and is heldin proper alignment by guide flange 314. The surface contour of pushermember 340 is made to suit the desired curve of frame 310 in its normaloperating position. The actuating means for pusher 340 is similar to theactuating means for the embodiments shown in FIGS. 6 and 7, and consistsof a hydraulic cylinder (not shown), a piston rod 342 attached to thebracket 344 which is fixed to pusher 340, and a pair of tracks 346 whichare an integral part of pusher 340 and each co-act with flanged guidewheels 348, which are mounted for rotation in fixed structures.

Because the casting in normal operation according to this invention hasa liquid core after it passes through the lower pinch roll stand 42, itis not possible to severe this casting with the usual cutting torch asit descends vertically below the pinch rolls. According to theconventional practice, the casting is severed a short distance above thetop of the starter bar, and then the starter bar with this short lengthof casting is lowered vertically. The remainder of the casting may becut into lengths and lowered vertically or may be deflected into acurved path according to means presently known in the art. Opera tionaccording to this invention requires separation of the casting from thestarter bar without cutting the casting, so that the starter bar maydescend vertically while the casting is bent by bending means 60 anddeflected and guided in a curved path by the guide frame 90 of thisinvention.

The starter bars used in the present invention may comprise an elongatedmetal body having a metallic chill plate releasably secured to the topthereof. One such starter bar is illustrated in FIGS. 9 to 11. Thisstarter bar is described in greater detail and claimed in the copendingapplication of Justin E. Foldessy and Francis Gallucci, Ser. No.333,383, filed Dec. 26, 1963, now Patent No. 3,266,104, issued Aug. 16,1966, and entitled Continuous Casting Apparatus Having a QuicklyDisconnectable Starter Bar.

Referring now to FIGS. 9 to 11, starter bar 26, which is adapted to beinserted into the lower end of tubular open-ended continuous castingmold 20 as indicated in 7 FIG. 1, is an elongated metal body having ametallic chill plate 24 releasably secured to the upper end thereof.

This metallic chill plate is approximately to /2" thick. It protects thestarter bar 26 from direct contact with molten metal poured into themold. Chill plate 24 has a plurality of cylindrical pins 350 weldedthereto. Pins 350 have heads 352 above the chill plate for gripping thecasting in an interlocking grip, and also have necked portions 354 belowthe chill plate. The starter bar 26 has a T-shaped transverse passage366 extending therethrough from one edge wall 368 to the opposite edgewall 370 and holes in the upper end to receive pins 350. A rectangularslide plate 376 is slidable in channel 366. Slide plate 376 has aplurality of slots 378 which engage necked portions 354 of pins 350 soas to secure chill plate 24 to bar 26 when the slide plate 376 is in theposition shown and to release bar 26 from chill plate 24 and theattached casting when the slide plate 376 is moved to the left. Theslots 378 have circular portions 380 which are slightly larger indiameter than pins 350, and oblong portions 382 are narrower than thediameter of pins 350 but slightly wider than the necked portions 354. Aflange 384 attached to slide plate 376, and a limit stop 386, limit theextent of sliding movement of slide plate 376. Piston rod 54 strikesslide plate 376 when this slide plate reaches the elevation at whichthis piston rod is located. This causes sliding movement of slide plate376 to the left to release the starter bar 26 from chill plate 24. Thestarter bar may then be lowered at a speed greater than that at whichchill plate 24 and the attached casting descends. Starter bar 26 alsomay have an indentation 400 in at least one edge for receiving pistonrod '58 and thereby setting actuating means 50 into operation.

An atlernative starter bar which is useful in this invention is thatdescribed and claimed in the copending application of Justin E. Foldessyand Andrew L. Poulos, Ser. No. 333,449, filed Dec. 26, 1963, now PatentNo. 3,274,653, issued Sept. 27, 1966, entitled Quickly DisconnectableStarter Bar.

Disconnection of starter bar 26 from plate 24 in the attached casting isaccomplished by a striker arm 54 striking slide plate 376 in starter bar26 when the slide plate reaches the predetermined elevation at whichstriker arm 54 and cylinder 52 are located. This cylinder is fixedlymounted between the upper and lower pinch roll stands 40 and 42 as hasbeen indicated. Striker arm 54 is normally retracted away from starterbar 26 as shown in FIG. 1. T 0 release starter bar 26 from chill plate24, piston 53 and striker arm 54 are moved toward the path of thestarter bar and casting. When the striker arm 54 reaches the limit ofits travel in this direction, it strikes slide plate 376 moving it tothe left and releasing starter bar 25 from chill plate 24. Striker arm54 is then retracted. Striker arm 54 can be operated in any desiredmanner. In a preferred embodiment, which will now be described, arm 54is operated automatically when starter bar 26 reaches a predeterminedelevation.

FIG. 12 schematically illustrates a preferred electromechanicalautomatic actuation system 50 whose function is to release starter bar26 from plate 24. All components are shown in the de-energized position.

Air cylinders 52 and 56 are conrolled by solenoid operated air valves450 and 452 respectively. Solenoid valve 450 has a connection 454 forthe supply of air under pressure, a pair of exhaust connections 456, andconnections 458 and 460 leading to either end of cylinder 52. Solenoidoperated valve 452 is of identical construction having an air supplypassage 462, a pair of air exhaust passages 464, and a pair ofconnections 466 and 468 leading to the respective ends of cylinder 56.

Operation of solenoid operated valves 450 and 452 is controlled by thestate of the contacts associated with control relays 470 and 472 andtiming relay 474. Current for the electrical system is supplied from apower source (not shown) through electrical lines 476 and 478.

1 1 Switch 480 is located in line 476. When this switch 480 is closed,the actuation system 50 is supplied with power and is in condition to beoperated.

Operation of system 50 is initiated by pushing one of the two parallelpush buttons 482 and 484, both of which are normally open, to closedposition. When one of the push buttons is closed, relay 470 isenergized, thereby closing the normally open contacts 470a and 4711b.The closing of contact 47Gb energizes the solenoid controlled air valve452 so as to supply air pressure from supply line 462 to cylinder 56through line 468 so as to extend the sensing arm 58 forward sufficientlyto contact and ride on the edge of the starter bar 26. It should benoted that when the sensing arm 58 is thus extended forward, the limitswitch 59 is moved to the dotted line position 59a, in which position itis still open. Closing of switch 59 requires a further forward extensionof the sensing arm 58.

Contact 470a closes to provide a holding action so that when the pushbutton 482 or 484 is released, the relay 470 will remain energized bycurrent flowing between the lines 476 and 478 through the normallyclosed contact 472a, the now closed holding contact 470a, and the relaycoil 470. The two buttons 486 which are in this path of current flow arekept normally closed and are simply included for safety purposes topermit manually stopping the operation of this actuation system 50 attwo different locations. Accordingly, the manual release of buttons 482and 484 will, because of the action of this holding contact 470a, leavethe sensing arm 58 projected in a forward direction to ride on thestarter bar 26.

As the starter bar 26 descends, the sensing arm 58 will ride into theindentation 400, thereby causing the sensing arm 58 to project furtherforward (to the left in FIG. 12) so as to close the limit switch 59(shown by the dotted line position 59b). As a consequence, relay 472 isenergized through the now closed limit switch 59 and the normally closedcontact 474a, which is controlled by timing relay 474 as will behereinafter explained.

When relay 472 is energized, normally open contact 472b is moved to theclosed position, which in turn energizes solenoid operated air valve450. This causes air under pressure from supply line 450 to beintroduced into air cylinder 52 via connection 460, which moves thepiston 53 in cylinder 52 and forces the striker arm 54 forward (to theleft in FIG. 9) with suificient force so that the arm 54 will strike theslide plate 376, causing the slide plate 376 to move it to the left asseen in FIG. 9 sufficiently to disengage the starter bar 26 from chillplate 24 and the lower end of the casting. The sensing arm 58 andstriker arm 54 are spaced from one another the same distance apart asare the indentation 400 and the slide plate 376, so that the entrance ofthe sensing arm 58 into the indentation 400 results in the actuation ofthe striker arm 54 at just the appropriate time to cause the arm 54 tohit the slide plate 376.

The closing of the limit switch 59 also energizes the timing relay 474,the coil of which is arranged in parallel with the coil of the relay472. Energizing of the timing relay 474 closes the normally open contact4741), which contacts 474b then operates as a holding contact for boththe relay 472 and the timing relay 474 so that when the sensing arm 58rides out of the indentation 400, due to the downward motion of thestarter bar 26, the limit switch 59 may open without tie-energizing therelay 472 and timing relay 474. The contact 474a is a normally closedcontact which is associated with the timing relay 474 but whose state isnot affected by the state of the timing relay 474.

When the timing relay 474 has been energized, it starts on apredetermined timing cycle, at the end of which the timing relay 474mechanically opens the contacts 474a through mechanical linkage 474e,thereby deenergizing the relay 472 and the timing relay 474.

While the timing relay 474 is running through its preset time cycle, itas well as relay 472 remain energized.

Normally open contacts 472]; are closed by the energizing of the relay472 and remain closed during the timing cycle. Therefore, solenoidoperated air valve 450 remains energized and striker arm 54 remains inis forward position (to the left in FIG. 12) while timing relay 474 isrunning through its preset timing cycle. The duration of this timingcycle is normally not over about two seconds.

Once the timing relay 474 has run its cycle, it mechanically openscontact 474a so as to de-energize both timing relay 474 and controlrelay 472. De-energizing of relay 472 causes contact 47211 to revert toits normally open position and thus de-energize the solenoid actuatedair valve 450. De-energizing of the solenoid actuated air valve 450causes the air cylinder 52 to switch and retract the striker arm 54 toits normally retracted position free of the starter bar 26 andthecasting.

Energizing of relay 472 as a consequence of the sensing arm 58 enteringthe indentation 400 also acts to open the normally closed contacts 472a,thereby de-energizing the relay 470. This de-enegizing of the relay 470opens normally open contacts 47% thereby de-energizing the solenoidactuated air valve 452 and causing the air cylinder 56 to switch andconsequently retract the sensing arm 58. Thus the sensing arm 58 isretracted and moved out of the way of the starter bar 26 and the castingimmediately after it has entered the indentation 400 and this retractionof the sensing arm 58 is achieved automatically.

After the timing relay 474 has gone through its timing cycle and causedthe normally closed contact 474a to open, the timing relay 474 isde-energized and resets itself resulting in the normally open contact4741; opening and the normally closed contact 474a reclosing. In thisfashion actuation system 50 returns to its initial state, that being thestate illustrated in FIG. 12. It shouldv be noted that in this initialstate all of the relays 470, 472 and 474 are de-energized so that thecontacts shown are in their normal position. It should also be notedthat in this initial state the solenoid actuated air valves 450 and 452are de-energized and place air pressure in the cylinders 52 and 56 insuch a fashion as to cause the sensing arm 58 and striker arm 54 to bein their re tracted positions (to the right in FIG. 12.)

It should be understood that FIG. 12 is a somewhat simplified schematicdrawing of automatic actuation sys tem 50. Additional safety buttons,fuses, meters and the like may be employed to provide information andmonitoring of the operation of this automatic actuationsystem.

Other automatic actuation systems besides the one illustrated can beused. If desired, the sensing mechanism including cylinder 56 andsensing arm 58 can be omitted and the admission of fluid under pressureto cylinder 52 can be under the control of an operator.

Operation according to this invention will now be described withparticular reference to FIG. 1. Prior to the start of a casting, theupper end of starter bar and chill plate attached are inserted into thelower end of an open-ended tubular continuous casting mold 20. Moltenmetal is then poured into the mold until it reaches a predeterminedelevation near the top thereof. When this predetermined elevation isreached, the starter bar and the casting attached thereto are slowlybrought downward at a uniform rate under the control of pinch rollassemblies 40 and 42. The outer surface of the casting, and the lowerend of the casting which abuts the chill Plate, solidify while thecasting is still in the mold and before movement-of the starter bardownwardly is commenced.

After the height of metal in the mold has reached a predetermined level,the starter bar and the casting are brought slowly downward until thestarter bar reaches the predetermined elevation at which it isdisconnected from the casting by actuation system 50. The upper pinchrolls 40 may be accelerated to rotate at a slightly greater speed thanthe lower pinch rolls 42 at this time, so as 13 to maintain a slightcompression on the casting and the starter bar. A slight compression onthe starter bar facilitates disconnection of the starter bar from thechill plate and casting.

The starter bar, being of substantial length and inflexible, must bebrought straight downwardly by suitable means such as travelingreceptacle 80. The starter bar is then brought rapidly downward, whilethe casting and the chill plate continue to descend at the slow ratestill under the control of pinch rolls 40 and 42. From the time thestarter bar is inserted into the bottom of the mold prior to pouring,until the starter bar has been disconnected and lowered below the pathof the retractable section 92, the retractable section is in theretracted position as shown in dotted line position in FIG. 4. Thispermits unimpeded vertical descent of the starter bar.

After the starter bar has been taken out of the Way, the castingcontinues to descend through the lower pinch roll stand 42 and bendingmeans 60. In contrast to presently known continuous casting operationsin which the casting is completely solidified before it is bent, thecasting in the present invention has a core of molten metal, as itenters bending means 60 in the normal mode of operation. The casting isdeflected slightly from its vertical line of travel while in bendingmeans 60. Before the casting emerges from the lower end of bending means60, the retractable section 92 is retracted from its dotted lineposition to its normal operating or solid line position as shown in FIG.4 so as to receive the casting as it emerges from the lower end ofbending means 60.

The casting continues to descend successively through the upper andlower sections 92 and 94 of curved guide frame 90, being guided by theguide rolls therein as it descends. The casting still has a liquid coreas it enters guide frame 90 and it is cooled by water sprays 100 so asto solidify this liquid core before the casting emerges from the lowerend of the fixed section 94 of guide frame 90. The casting may befurther processed as desired.

An important advantage of the present invention is that it is possibleto cast metal continuously in an apparatus having less height than theusual continuous casting apparatus. Presently it is considered necessaryto solidify the casting completely while it is still traveling in thevertical cooling section directly below the mold and before reaching thepinch rolls. Now it is found that such procedure is not necessary.Instead, partial solidification in the cooling zone directly below themold is sufficient, and solidification can be completed in a secondcooling zone in which the casting is guided in a curved rather than avertical path. This makes it possible to operate with a vertical coolingzone of considerably less height than was heretofore thought possible.

While this invention has been described with reference to specificembodiments thereof, it is understood that the scope shall be measuredonly by the scopee of the appended claims.

I claim:

1. In continuous metal casting apparatus comprising a generallyvertically extending mold having an upper opening for the introductionof molten metal to form a casting and a lower discharge passage throughwhich said casting may descend continuously as it is formed, theimprovement comprising a plurality of pinch rolls arranged in a pair ofvertical rows and adapted to engage a pair of opposite faces of saidcasting for controlling the speed of descent thereof, back-up roll meansincluding a plurality of backup rolls engaging and supporting said pinchrolls, and motor means for driving said back-up rolls and therebydriving said pinch rolls in frictional engagement with said back-uprolls to control the speed of said casting.

2. The apparatus of claim 1 wherein said pinch rolls are furtherarranged in an upper assembly and a lower assembly, the pinch rolls ofone of said assemblies being rotatable at a different speed from thepinch rolls of the other of said assemblies.

References Cited FOREIGN PATENTS 731,659 6/ 1955 Great Britain. 840,6767/ 1960 Great Britain. 932,196 7/ 1963 Great Britain.

1. SPENCER OVERHOLSER, Primary Examiner. R. SPENCER ANNEAR, AssistantExaminer.

U.S. Cl. X.R. 226-18 1 UNITED STATES PATENT OFFICE CERTIFICATE OFCORRECTION Patent No. 3,447,591 June 3 1969 Justin E. Foldessy It iscertified that error appears in the above identified patent and thatsaid Letters Patent are hereby corrected as shown below:

Column 1, line 13, continuopsly" should read continuously line 26, "1969should read 1967 Column 2, line 61, "casing" should read casting Column3, line 23, "isomeric" should read isometric Column 4, line 53,"genetrally should read generally Column 5, line 10, "its" should readis line 15, "thte should read the line 27, "vetrically" should readvertically Column 8, lines 7 and 23, "memebr" each occurrence, shouldread member line 35, "reciporcable" should read reciprocable Column 9,line 48, "severe" should read sever Column 11, line 42, "450" shouldread 454 line 60, "contacts" should read contact Column 14, line 10,"scopee" should read scope Signed and sealed this 21st day of April1970.

(SEAL) Attest:

WILLIAM E. SCHUYLER, JR.

Edward M. Fletcher, Jr.

Commissioner of Patents Attesting Officer

